Coordinated specialty care (CSC) provided in the early course of psychosis can reduce the long-term chronicity and dysfunction associated with schizophrenia-spectrum disorders. However, few young adults with early psychosis (EP) are engaged with these programs. Young adults with EP are particularly susceptible to stigma and negative beliefs about psychiatric treatment, and thus are often apprehensive to present to in- person care. Despite their reluctance to seek services, young adults with EP often engage with mental health resources through online and mobile technologies. Several digital health interventions have been developed as adjuncts to in-person services for this population and have demonstrated feasibility, acceptability and preliminary efficacy. However, there are few available digital health tools designed for young adults with EP who are not connected to in-person care. In the absence of such tools, individuals often turn to social media or forums that often reify stigmatizing beliefs or discourage help seeking. Mobile health interventions appear particularly well suited to this population given the fact that mobile devices are the primary media source for most young adults and can provide individualized, real-time, real-place support to introduce users to psychosocial interventions involved in CSC. It remains unclear at present, however, whether and how remotely delivered mHealth can be leveraged to increase engagement in treatment for young adults with EP. The proposed research project proposes to develop and test an mHealth intervention designed to impact help-seeking beliefs through psychoeducation, stigma-reducing content, stress management exercises, and locally relevant treatment information delivered through audio, video, and automated motivational text interactions, and personalized through ecological momentary assessment (EMA). This project will take a user- centered design approach with individuals who are both engaged and unengaged in treatment, including (1) a contextual inquiry to understand barriers, interests and preferences related to mHealth and in-person treatment, (2) development, refinement and usability testing, and (3) a pilot randomized controlled trial assessing feasibility, acceptability and preliminary efficacy compared to an active control mHealth intervention providing only stress management. This research project will provide a central piece of the candidate's overall training plan. This K23 career development award provides training to support an independent research program developing interventions that reduce barriers to care for young adults with EP. This includes three training areas, including (1) mobile health targeting increasing mental health care engagement, (2) user-centered design, and (3) advanced longitudinal models and quantitative methods for digital health trials. These goals will be met through expert mentorship, didactic training, coursework, and the successful completion of the research project.